Hey Torog, how's it going? Well with my grinder, I leave the stems on if they are small, but pull out larger ones. Don't have the seed problem though. I just smoke sensimillia, but I'd take them out first. I have that 4 piece mixnball grinder, it grinds up the bud pretty well and keeps most of the stem pieces out of the finished bud. After I grind it, I shake it and tap the grinder on a table, and when I unscrew the bottom there is a nice bit of keif there to scoop out.